[gnome-builder] meson: Remove reference to non-existent file

[Emmanuele Bassi <ebassi src gnome org>]

commit 7025cc26b9cec864b5a49639f40696470faa2913
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Feb 22 15:39:14 2017 +0000

    meson: Remove reference to non-existent file
    
    The doc/reference/libide directory was removed recently.

 meson.build |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/meson.build b/meson.build
index 4832112..f65514e 100644
--- a/meson.build
+++ b/meson.build
@@ -150,7 +150,6 @@ subdir('contrib/tmpl')
 subdir('contrib/xml')
 subdir('contrib/gstyle') # Depends on libsearch/libxml
 subdir('libide')
-subdir('doc/reference/libide')
 subdir('help')
 subdir('plugins')
 subdir('po')